The present invention generally relates to magnetic ink character recognition. More particularly, the invention relates to a read head assembly and method for recognizing magnetic ink characters that involves the dimensional scaling of MICR peak information of a first waveform based on a second waveform. MICR peak information includes information regarding the relative amplitude of each peak and the relative position of each peak.
Banks, credit unions and other financial institutions regularly process checks, deposit slips, and other types of bank documents in order to execute financial transactions efficiently. Document processing systems have therefore become quite prevalent in the industry. Typically, information will be printed on these documents in magnetic ink that can be read both by the human eye and a computer. This form of printing is read by a process termed xe2x80x9cmagnetic ink character recognitionxe2x80x9d (MICR). As part of the recognition process, a MICR magnetic read head is used to read the information printed on the document. The American National Standards Institute with the American Bankers Association as Secretariat has promulgated print and test specifications for this magnetic ink printing.
Conventional approaches to MICR generally involve the step of determining peak information for a waveform generated by the magnetic read head. This peak information typically includes information regarding the amount of time between the peaks of each character. Knowledge of the velocity of the document (and thus, the character contained therein) allows this time information to be converted into distance information, which can be compared to each MICR character and their peak profiles as contained in the ANS X9.27-2000 xe2x80x9cPrint and Test Specifications for Magnetic Ink Printing (MICR)xe2x80x9d as promulgated by the American National Standards Institute.
The above approach is acceptable if the velocity of the document is either known or can be controlled. In fact, conventional approaches to MICR typically involve rather complex schemes for controlling the velocity of the document or attempting to measure its velocity at different times as the document moves past the MICR read head. It is easy to understand that these schemes have a tendency to increase design, processing, and manufacturing costs. It is therefore desirable to provide a system and method for recognizing a magnetic ink character printed on a document that does not require knowledge or control of document velocity.
In a first aspect of the invention, a method for recognizing a magnetic ink character printed on a document is provided. The method includes the step of determining peak position information for a MICR character based on a first waveform, where the first waveform is generated in response to a magnetic field of the character. The method further provides for dimensionally scaling the peak information in the x dimension based on the first waveform and a second waveform, wherein the second waveform is also generated in response to the magnetic field of a MICR character. The dimensionally scaled peak position information with its relative amplitude is then compared to peak position and amplitude profiles, where the peak profiles correspond to known magnetic ink characters. Dimensionally scaling the peak position information based on a second waveform eliminates the need for precise knowledge or control of the document velocity.
In a second aspect of the invention, a method for dimensionally scaling peak position information based on a scaling waveform, where the scaling waveform is generated by a dimensionally scaling read head, is provided. The method includes the step of determining a known head to head spacing, where the known head to head spacing defines a distance between a measurement read head and the scaling read head. The measurement read head generates a measurement waveform in response to the magnetic field of the magnetic ink character. A measured head to scaling head spacing is then determined based on the measurement waveform and the scaling waveform. The method further provides for dimensionally scaled peak position information to be calculated based on the spacing between the known head and the measured head.
In another aspect of the invention, a read head assembly for a magnetic ink character recognition system is provided. The read head assembly includes a first read head for generating a first waveform in response to a magnetic field of a magnetic ink character printed on a document. A second read head generates a second waveform in response to the magnetic field of the magnetic ink character. The read heads have a known head to head spacing, where the known head to head spacing defines an actual distance between the first read head and the second read head.